[PATCHv v3] tools lib traceevent: Add support for IP address formats

From: David Ahern
Date: Thu Dec 18 2014 - 20:43:23 EST


Adds helper for following kernel formats:
%pi4 print an IPv4 address with leading zeros
%pI4 print an IPv4 address without leading zeros
%pi6 print an IPv6 address without colons
%pI6 print an IPv6 address with colons
%pI6c print an IPv6 address with colons
%pISpc print an IP address from a sockaddr

Allows these formats to be used in tracepoints.

Quite a bit of this is adapted from code in lib/vsprintf.c.

v3:
- use of 'c' and 'p' requires 'I'

v2:
- pass ptr+1 to print_ip_arg per Namhyung's comments
- added field length checks to sockaddr function

Signed-off-by: David Ahern <dsahern@xxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
tools/lib/traceevent/event-parse.c | 328 +++++++++++++++++++++++++++++++++++++
1 file changed, 328 insertions(+)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index cf3a44bf1ec3..afe20ed9fac8 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -32,6 +32,7 @@
#include <stdint.h>
#include <limits.h>

+#include <netinet/ip6.h>
#include "event-parse.h"
#include "event-utils.h"

@@ -4149,6 +4150,324 @@ static void print_mac_arg(struct trace_seq *s, int mac, void *data, int size,
trace_seq_printf(s, fmt, buf[0], buf[1], buf[2], buf[3], buf[4], buf[5]);
}

+static void print_ip4_addr(struct trace_seq *s, char i, unsigned char *buf)
+{
+ const char *fmt;
+
+ if (i == 'i')
+ fmt = "%03d.%03d.%03d.%03d";
+ else
+ fmt = "%d.%d.%d.%d";
+
+ trace_seq_printf(s, fmt, buf[0], buf[1], buf[2], buf[3]);
+}
+
+static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
+{
+ return ((unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
+ (unsigned long)(a->s6_addr32[2] ^ htonl(0x0000ffff))) == 0UL;
+}
+
+static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
+{
+ return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
+}
+
+static void print_ip6c_addr(struct trace_seq *s, unsigned char *addr)
+{
+ int i, j, range;
+ unsigned char zerolength[8];
+ int longest = 1;
+ int colonpos = -1;
+ uint16_t word;
+ uint8_t hi, lo;
+ bool needcolon = false;
+ bool useIPv4;
+ struct in6_addr in6;
+
+ memcpy(&in6, addr, sizeof(struct in6_addr));
+
+ useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
+
+ memset(zerolength, 0, sizeof(zerolength));
+
+ if (useIPv4)
+ range = 6;
+ else
+ range = 8;
+
+ /* find position of longest 0 run */
+ for (i = 0; i < range; i++) {
+ for (j = i; j < range; j++) {
+ if (in6.s6_addr16[j] != 0)
+ break;
+ zerolength[i]++;
+ }
+ }
+ for (i = 0; i < range; i++) {
+ if (zerolength[i] > longest) {
+ longest = zerolength[i];
+ colonpos = i;
+ }
+ }
+ if (longest == 1) /* don't compress a single 0 */
+ colonpos = -1;
+
+ /* emit address */
+ for (i = 0; i < range; i++) {
+ if (i == colonpos) {
+ if (needcolon || i == 0)
+ trace_seq_printf(s, ":");
+ trace_seq_printf(s, ":");
+ needcolon = false;
+ i += longest - 1;
+ continue;
+ }
+ if (needcolon) {
+ trace_seq_printf(s, ":");
+ needcolon = false;
+ }
+ /* hex u16 without leading 0s */
+ word = ntohs(in6.s6_addr16[i]);
+ hi = word >> 8;
+ lo = word & 0xff;
+ if (hi)
+ trace_seq_printf(s, "%x%02x", hi, lo);
+ else
+ trace_seq_printf(s, "%x", lo);
+
+ needcolon = true;
+ }
+
+ if (useIPv4) {
+ if (needcolon)
+ trace_seq_printf(s, ":");
+ print_ip4_addr(s, 'I', &in6.s6_addr[12]);
+ }
+
+ return;
+}
+
+static void print_ip6_addr(struct trace_seq *s, char i, unsigned char *buf)
+{
+ int j;
+
+ for (j = 0; j < 16; j += 2) {
+ trace_seq_printf(s, "%02x%02x", buf[j], buf[j+1]);
+ if (i == 'I' && j < 14)
+ trace_seq_printf(s, ":");
+ }
+}
+
+/*
+ * %pi4 print an IPv4 address with leading zeros
+ * %pI4 print an IPv4 address without leading zeros
+ * %pi6 print an IPv6 address without colons
+ * %pI6 print an IPv6 address with colons
+ * %pI6c print an IPv6 address in compressed form with colons
+ * %pISpc print an IP address based on sockaddr; p adds port.
+ */
+static int print_ipv4_arg(struct trace_seq *s, const char *ptr, char i,
+ void *data, int size, struct event_format *event,
+ struct print_arg *arg)
+{
+ unsigned char *buf;
+
+ if (arg->type == PRINT_FUNC) {
+ process_defined_func(s, data, size, event, arg);
+ return 0;
+ }
+
+ if (arg->type != PRINT_FIELD) {
+ trace_seq_printf(s, "ARG TYPE NOT FIELD BUT %d", arg->type);
+ return 0;
+ }
+
+ if (!arg->field.field) {
+ arg->field.field =
+ pevent_find_any_field(event, arg->field.name);
+ if (!arg->field.field) {
+ do_warning("%s: field %s not found",
+ __func__, arg->field.name);
+ return 0;
+ }
+ }
+
+ buf = data + arg->field.field->offset;
+
+ if (arg->field.field->size != 4) {
+ trace_seq_printf(s, "INVALIDIPv4");
+ return 0;
+ }
+ print_ip4_addr(s, i, buf);
+
+ return 0;
+}
+
+static int print_ipv6_arg(struct trace_seq *s, const char *ptr, char i,
+ void *data, int size, struct event_format *event,
+ struct print_arg *arg)
+{
+ char have_c = 0;
+ unsigned char *buf;
+ int rc = 0;
+
+ /* pI6c */
+ if (i == 'I' && *ptr == 'c') {
+ have_c = 1;
+ ptr++;
+ rc++;
+ }
+
+ if (arg->type == PRINT_FUNC) {
+ process_defined_func(s, data, size, event, arg);
+ return rc;
+ }
+
+ if (arg->type != PRINT_FIELD) {
+ trace_seq_printf(s, "ARG TYPE NOT FIELD BUT %d", arg->type);
+ return rc;
+ }
+
+ if (!arg->field.field) {
+ arg->field.field =
+ pevent_find_any_field(event, arg->field.name);
+ if (!arg->field.field) {
+ do_warning("%s: field %s not found",
+ __func__, arg->field.name);
+ return rc;
+ }
+ }
+
+ buf = data + arg->field.field->offset;
+
+ if (arg->field.field->size != 16) {
+ trace_seq_printf(s, "INVALIDIPv6");
+ return rc;
+ }
+
+ if (have_c)
+ print_ip6c_addr(s, buf);
+ else
+ print_ip6_addr(s, i, buf);
+
+ return rc;
+}
+
+static int print_ipsa_arg(struct trace_seq *s, const char *ptr, char i,
+ void *data, int size, struct event_format *event,
+ struct print_arg *arg)
+{
+ char have_c = 0, have_p = 0;
+ unsigned char *buf;
+ struct sockaddr_storage *sa;
+ int rc = 0;
+
+ /* pISpc */
+ if (i == 'I') {
+ if (*ptr == 'p') {
+ have_p = 1;
+ ptr++;
+ rc++;
+ }
+ if (*ptr == 'c') {
+ have_c = 1;
+ ptr++;
+ rc++;
+ }
+ }
+
+ if (arg->type == PRINT_FUNC) {
+ process_defined_func(s, data, size, event, arg);
+ return rc;
+ }
+
+ if (arg->type != PRINT_FIELD) {
+ trace_seq_printf(s, "ARG TYPE NOT FIELD BUT %d", arg->type);
+ return rc;
+ }
+
+ if (!arg->field.field) {
+ arg->field.field =
+ pevent_find_any_field(event, arg->field.name);
+ if (!arg->field.field) {
+ do_warning("%s: field %s not found",
+ __func__, arg->field.name);
+ return rc;
+ }
+ }
+
+ sa = (struct sockaddr_storage *) (data + arg->field.field->offset);
+
+ if (sa->ss_family == AF_INET) {
+ struct sockaddr_in *sa4 = (struct sockaddr_in *) sa;
+
+ if (arg->field.field->size < sizeof(struct sockaddr_in)) {
+ trace_seq_printf(s, "INVALIDIPv4");
+ return rc;
+ }
+
+ print_ip4_addr(s, i, (unsigned char *) &sa4->sin_addr);
+ if (have_p)
+ trace_seq_printf(s, ":%d", ntohs(sa4->sin_port));
+
+
+ } else if (sa->ss_family == AF_INET6) {
+ struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *) sa;
+
+ if (arg->field.field->size < sizeof(struct sockaddr_in6)) {
+ trace_seq_printf(s, "INVALIDIPv6");
+ return rc;
+ }
+
+ if (have_p)
+ trace_seq_printf(s, "[");
+
+ buf = (unsigned char *) &sa6->sin6_addr;
+ if (have_c)
+ print_ip6c_addr(s, buf);
+ else
+ print_ip6_addr(s, i, buf);
+
+ if (have_p)
+ trace_seq_printf(s, "]:%d", ntohs(sa6->sin6_port));
+ }
+
+ return rc;
+}
+
+static int print_ip_arg(struct trace_seq *s, const char *ptr,
+ void *data, int size, struct event_format *event,
+ struct print_arg *arg)
+{
+ char i = *ptr; /* 'i' or 'I' */
+ char ver;
+ int rc = 0;
+
+ ptr++;
+ rc++;
+
+ ver = *ptr;
+ ptr++;
+ rc++;
+
+ switch (ver) {
+ case '4':
+ rc += print_ipv4_arg(s, ptr, i, data, size, event, arg);
+ break;
+ case '6':
+ rc += print_ipv6_arg(s, ptr, i, data, size, event, arg);
+ break;
+ case 'S':
+ rc += print_ipsa_arg(s, ptr, i, data, size, event, arg);
+ break;
+ default:
+ return 0;
+ }
+
+ return rc;
+}
+
static int is_printable_array(char *p, unsigned int len)
{
unsigned int i;
@@ -4337,6 +4656,15 @@ static void pretty_print(struct trace_seq *s, void *data, int size, struct event
ptr++;
arg = arg->next;
break;
+ } else if (*(ptr+1) == 'I' || *(ptr+1) == 'i') {
+ int n;
+
+ n = print_ip_arg(s, ptr+1, data, size, event, arg);
+ if (n > 0) {
+ ptr += n;
+ arg = arg->next;
+ break;
+ }
}

/* fall through */
--
1.9.3 (Apple Git-50)

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